As the IDF completes the work of neutralizing more than 30 “attack tunnels,” dug by Hamas under the southern border, the spotlight is also turning to the threat of subterranean terrorism originating from Hezbollah in the north.

The Lebanese Shiite organization has used tunnels and underground bunkers in its guerrilla warfare against Israel ever since the IDF withdrawal from southern Lebanon in May 2000. The heightened concern now is that Hezbollah may have expanded its network of internal tunnels inside south Lebanon, to enable attempts at offensive infiltration into Israel.

Last week, Prime Minister Benjamin Netanyahu said that the Hamas cross-border tunnel network had “catastrophic” potential, and 11 IDF soldiers have been killed during Operation Protective Edge by gunmen emerging from those tunnels into southern Israel near army positions, kibbutzim and moshavim, even as the IDF raced to demolish them.

Residents of Israeli communities on the Lebanese border, such as Kibbutz Gesher Haziv and the town of Kiryat Shmona, have in the past reported hearing muffled sounds underground, which they believe indicate Hezbollah tunnel digging. Now, though, such reports are gaining new resonance. Kiryat Shmona Mayor Nissim Malka sent Defense Minister Moshe Ya’alon an urgent appeal last week to investigate the matter. Apparently, the Israeli security establishment is taking the concerns extremely seriously.

The Defense Ministry’s Administration for the Development of Weapons and Technological Infrastructure recently approached geologists at Tel Aviv University, requesting assistance in helping track possible Hezbollah tunnel activity on the border. The project being commissioned will cost millions of shekels and will unfold over several years, Israel’s Channel 2 News reported on Sunday.

“The security establishment doesn’t want to repeat the mistakes it made regarding tunnels in the Gaza Strip. It wants to find a quick solution, so as not to be caught with its pants down,” one member of the project told the TV station. “We cannot take lightly the possibility that Hezbollah has dug a network of tunnels from the Lebanese border into Israel.”

A photo released by the IDF Spokesperson showing a tunnel found in the Northern Gaza Strip by IDF forces, August 3, 2014. (photo credit: IDF Spokesperson’s Unit/Flash90)

A well-placed Israeli government source suggested that the geology on the Lebanon-Israel border made tunneling a far more complex enterprise than in the sandy terrain of Gaza. But a geologist who spoke to Channel 2 said tunneling the rocky terrain of southern Lebanon is not as difficult as it may seem. A cross-border tunnel, hundreds of meters long, could take as little as six months to dig, he said.

Whether for reasons of psychological warfare or in all honesty, Hezbollah is also eager to substantiate Israeli fears. An article published on the movement’s website, al-Manar, on June 15, citing “security elements,” spoke of hundreds of booby-trapped tunnels prepared by Hezbollah over the past two years inside southern Lebanon, allowing fighters to move easily from place to place during battle.

“The most dangerous of these tunnels are those designated for infiltration,” claims the al-Manar article. “From time to time, Israel uses huge engineering vehicles to induce tremors in certain areas and help collapse these tunnels. However, there remain a number of tunnels which the Israeli army has not yet succeeded in disabling.”

Israel has not ruled out the existence of offensive tunnels on its border with Lebanon, but has not detected any yet, a spokesman for the IDF told The Times of Israel in a written message.

‘As of now, in every case in which suspicions regarding a tunnel existed, specially trained forces were deployed and did not identify any tunnels or access shafts,’ an IDF spokesman said

“The IDF conducts routine security operations along the northern border, including both defensive and intelligence operations that take into account that tunnels are on the spectrum of threats in the theater,” the message read. “As of now, in every case in which suspicions regarding a tunnel existed, specially trained forces were deployed and did not identify any tunnels or access shafts. These efforts are combined with technological solutions in order to ensure that no tunnels exist. Future force building plans also include further technological advances for tunnel detection.”

Eado Hecht, a specialist in military doctrine at the Begin-Sadat Center for Strategic Studies at Bar-Ilan University, said he had no knowledge of cross-border tunnels dug by Hezbollah, though the movement has certainly dug tunnels inside Lebanese territory to be used for cover and as launching pads for military operations. There have also been anecdotal reports of rocket launchers that were accessible from underground in the 2006 Second Lebanon War, he added.

“It’s not impossible that there are also offensive tunnels on the northern border,” he told The Times of Israel. “There are many indications of ties between Hezbollah and the North Koreans, who have dug such things. The Americans and South Koreans have already found four such tunnels on the border between North and South Korea, and they estimate that 20 more exist.”

Did Hezbollah transfer technical know-how to Hamas? Hecht said that Gaza’s history of tunnel digging dates back almost 50 years, when, in the years following the 1967 Six Day War, residents of the coastal city began digging tunnels underneath their homes for guerrilla warfare against the IDF. In 2000, Gazans began digging tunnels into the Sinai Peninsula for the purpose of arms smuggling, and later the smuggling of commodities, taxed by Hamas.

In 2001, Hamas started using tunnels offensively against Israel; digging them next to IDF posts and placing explosives inside. But the most famous case of a Hamas “success” in using subterranean cross-border tunneling was the abduction of Corporal Gilad Shalit from near Kerem Shalom, in southern Israel, via a tunnel from Gaza on June 25, 2006.

“They have had their own experience for many years; they don’t need outside inspiration,” Hecht said. “Hamas really doesn’t need Hezbollah.”

Hamas has had so much experience with tunnels, in fact, that one officer told Channel 2 he believed that Hezbollah was actually on the receiving end of the information flow.

“I estimate, and this is something which is being discussed in the army, that Hamas has conveyed important information to Hezbollah on how to dig tunnels using various techniques, given the extensive experience it has accumulated over the past years,” claimed Hecht.

Still, if the technical details of tunnel digging may have moved from Gaza to Beirut, the inspiration for the type of guerrilla warfare currently undertaken by Hamas has certainly traveled in the opposite direction, said Matti Friedman, a former Times of Israel reporter who is currently completing a book on Israel’s military experience in Lebanon during the 1990s and its effects on Israeli society today.

A Hezbollah flag is hung outside the home of the Palestinian terrorist responsible for killing eight students at Yeshivat Mercaz Harav in Jerusalem on March 6, 2008. (photo credit: Flash90)

“Hamas’s entire strategy post-2000 was inspired by Hezbollah and by what happened in the 1990s, culminating in the Israeli withdrawal from southern Lebanon,” Friedman told The Times of Israel. Yellow Hezbollah flags began to appear in West Bank rallies during the Second Intifada, which erupted just four months after Israel’s withdrawal from Lebanon, he noted. Palestinian factions in Gaza and the West Bank, not only Hamas, began to closely imitate Hezbollah’s tactics.

“Stone throwing and Molotov cocktails gave way to roadside bombs, ambushes, and other tactics drawn from the Hezbollah playbook,” he said.

Matti Friedman (photo credit: Courtesy)

Official rhetoric on both sides of the equation reflects this infatuation with the Hezbollah model. In his 2010 book ‘Hizbullah: the Story from Within,’ Hezbollah deputy secretary-general Naim Qassam wrote that the Israeli withdrawal from Lebanon was “a light at the end of the Palestinian tunnel, a hope that liberation might be achieved by treading the path of resistance and martyrdom. What happened in Lebanon can be repeated in Palestine.”

Last month, Hamas official Osama Hamdan said that the exchange of knowledge between Hamas and Hezbollah on Israel is ongoing.

“The connection with Hezbollah and Iran is much stronger today than people tend to think,” Hamdan declared. “The connection with Hezbollah is several times better than what the optimistic people would expect.”

Hezbollah created the concept of a “resistance society” mobilized perpetually for war against Israel, Friedman noted. Its success in Lebanon against Israel gave Palestinians the belief that “if they keep at it long enough and don’t care how many casualties they suffer, in the end they’ll have victory.”